1 /* 2 * atmel-pcm.c -- ALSA PCM interface for the Atmel atmel SoC. 3 * 4 * Copyright (C) 2005 SAN People 5 * Copyright (C) 2008 Atmel 6 * 7 * Authors: Sedji Gaouaou <sedji.gaouaou@atmel.com> 8 * 9 * Based on at91-pcm. by: 10 * Frank Mandarino <fmandarino@endrelia.com> 11 * Copyright 2006 Endrelia Technologies Inc. 12 * 13 * Based on pxa2xx-pcm.c by: 14 * 15 * Author: Nicolas Pitre 16 * Created: Nov 30, 2004 17 * Copyright: (C) 2004 MontaVista Software, Inc. 18 * 19 * This program is free software; you can redistribute it and/or modify 20 * it under the terms of the GNU General Public License as published by 21 * the Free Software Foundation; either version 2 of the License, or 22 * (at your option) any later version. 23 * 24 * This program is distributed in the hope that it will be useful, 25 * but WITHOUT ANY WARRANTY; without even the implied warranty of 26 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 27 * GNU General Public License for more details. 28 * 29 * You should have received a copy of the GNU General Public License 30 * along with this program; if not, write to the Free Software 31 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 32 */ 33 34 #include <linux/module.h> 35 #include <linux/init.h> 36 #include <linux/platform_device.h> 37 #include <linux/slab.h> 38 #include <linux/dma-mapping.h> 39 #include <linux/atmel_pdc.h> 40 #include <linux/atmel-ssc.h> 41 42 #include <sound/core.h> 43 #include <sound/pcm.h> 44 #include <sound/pcm_params.h> 45 #include <sound/soc.h> 46 47 #include "atmel-pcm.h" 48 49 50 /*--------------------------------------------------------------------------*\ 51 * Hardware definition 52 \*--------------------------------------------------------------------------*/ 53 /* TODO: These values were taken from the AT91 platform driver, check 54 * them against real values for AT32 55 */ 56 static const struct snd_pcm_hardware atmel_pcm_hardware = { 57 .info = SNDRV_PCM_INFO_MMAP | 58 SNDRV_PCM_INFO_MMAP_VALID | 59 SNDRV_PCM_INFO_INTERLEAVED | 60 SNDRV_PCM_INFO_PAUSE, 61 .period_bytes_min = 32, 62 .period_bytes_max = 8192, 63 .periods_min = 2, 64 .periods_max = 1024, 65 .buffer_bytes_max = ATMEL_SSC_DMABUF_SIZE, 66 }; 67 68 69 /*--------------------------------------------------------------------------*\ 70 * Data types 71 \*--------------------------------------------------------------------------*/ 72 struct atmel_runtime_data { 73 struct atmel_pcm_dma_params *params; 74 dma_addr_t dma_buffer; /* physical address of dma buffer */ 75 dma_addr_t dma_buffer_end; /* first address beyond DMA buffer */ 76 size_t period_size; 77 78 dma_addr_t period_ptr; /* physical address of next period */ 79 }; 80 81 /*--------------------------------------------------------------------------*\ 82 * ISR 83 \*--------------------------------------------------------------------------*/ 84 static void atmel_pcm_dma_irq(u32 ssc_sr, 85 struct snd_pcm_substream *substream) 86 { 87 struct atmel_runtime_data *prtd = substream->runtime->private_data; 88 struct atmel_pcm_dma_params *params = prtd->params; 89 static int count; 90 91 count++; 92 93 if (ssc_sr & params->mask->ssc_endbuf) { 94 pr_warn("atmel-pcm: buffer %s on %s (SSC_SR=%#x, count=%d)\n", 95 substream->stream == SNDRV_PCM_STREAM_PLAYBACK 96 ? "underrun" : "overrun", 97 params->name, ssc_sr, count); 98 99 /* re-start the PDC */ 100 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, 101 params->mask->pdc_disable); 102 prtd->period_ptr += prtd->period_size; 103 if (prtd->period_ptr >= prtd->dma_buffer_end) 104 prtd->period_ptr = prtd->dma_buffer; 105 106 ssc_writex(params->ssc->regs, params->pdc->xpr, 107 prtd->period_ptr); 108 ssc_writex(params->ssc->regs, params->pdc->xcr, 109 prtd->period_size / params->pdc_xfer_size); 110 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, 111 params->mask->pdc_enable); 112 } 113 114 if (ssc_sr & params->mask->ssc_endx) { 115 /* Load the PDC next pointer and counter registers */ 116 prtd->period_ptr += prtd->period_size; 117 if (prtd->period_ptr >= prtd->dma_buffer_end) 118 prtd->period_ptr = prtd->dma_buffer; 119 120 ssc_writex(params->ssc->regs, params->pdc->xnpr, 121 prtd->period_ptr); 122 ssc_writex(params->ssc->regs, params->pdc->xncr, 123 prtd->period_size / params->pdc_xfer_size); 124 } 125 126 snd_pcm_period_elapsed(substream); 127 } 128 129 130 /*--------------------------------------------------------------------------*\ 131 * PCM operations 132 \*--------------------------------------------------------------------------*/ 133 static int atmel_pcm_hw_params(struct snd_pcm_substream *substream, 134 struct snd_pcm_hw_params *params) 135 { 136 struct snd_pcm_runtime *runtime = substream->runtime; 137 struct atmel_runtime_data *prtd = runtime->private_data; 138 struct snd_soc_pcm_runtime *rtd = substream->private_data; 139 140 /* this may get called several times by oss emulation 141 * with different params */ 142 143 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer); 144 runtime->dma_bytes = params_buffer_bytes(params); 145 146 prtd->params = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream); 147 prtd->params->dma_intr_handler = atmel_pcm_dma_irq; 148 149 prtd->dma_buffer = runtime->dma_addr; 150 prtd->dma_buffer_end = runtime->dma_addr + runtime->dma_bytes; 151 prtd->period_size = params_period_bytes(params); 152 153 pr_debug("atmel-pcm: " 154 "hw_params: DMA for %s initialized " 155 "(dma_bytes=%zu, period_size=%zu)\n", 156 prtd->params->name, 157 runtime->dma_bytes, 158 prtd->period_size); 159 return 0; 160 } 161 162 static int atmel_pcm_hw_free(struct snd_pcm_substream *substream) 163 { 164 struct atmel_runtime_data *prtd = substream->runtime->private_data; 165 struct atmel_pcm_dma_params *params = prtd->params; 166 167 if (params != NULL) { 168 ssc_writex(params->ssc->regs, SSC_PDC_PTCR, 169 params->mask->pdc_disable); 170 prtd->params->dma_intr_handler = NULL; 171 } 172 173 return 0; 174 } 175 176 static int atmel_pcm_prepare(struct snd_pcm_substream *substream) 177 { 178 struct atmel_runtime_data *prtd = substream->runtime->private_data; 179 struct atmel_pcm_dma_params *params = prtd->params; 180 181 ssc_writex(params->ssc->regs, SSC_IDR, 182 params->mask->ssc_endx | params->mask->ssc_endbuf); 183 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, 184 params->mask->pdc_disable); 185 return 0; 186 } 187 188 static int atmel_pcm_trigger(struct snd_pcm_substream *substream, 189 int cmd) 190 { 191 struct snd_pcm_runtime *rtd = substream->runtime; 192 struct atmel_runtime_data *prtd = rtd->private_data; 193 struct atmel_pcm_dma_params *params = prtd->params; 194 int ret = 0; 195 196 pr_debug("atmel-pcm:buffer_size = %ld," 197 "dma_area = %p, dma_bytes = %zu\n", 198 rtd->buffer_size, rtd->dma_area, rtd->dma_bytes); 199 200 switch (cmd) { 201 case SNDRV_PCM_TRIGGER_START: 202 prtd->period_ptr = prtd->dma_buffer; 203 204 ssc_writex(params->ssc->regs, params->pdc->xpr, 205 prtd->period_ptr); 206 ssc_writex(params->ssc->regs, params->pdc->xcr, 207 prtd->period_size / params->pdc_xfer_size); 208 209 prtd->period_ptr += prtd->period_size; 210 ssc_writex(params->ssc->regs, params->pdc->xnpr, 211 prtd->period_ptr); 212 ssc_writex(params->ssc->regs, params->pdc->xncr, 213 prtd->period_size / params->pdc_xfer_size); 214 215 pr_debug("atmel-pcm: trigger: " 216 "period_ptr=%lx, xpr=%u, " 217 "xcr=%u, xnpr=%u, xncr=%u\n", 218 (unsigned long)prtd->period_ptr, 219 ssc_readx(params->ssc->regs, params->pdc->xpr), 220 ssc_readx(params->ssc->regs, params->pdc->xcr), 221 ssc_readx(params->ssc->regs, params->pdc->xnpr), 222 ssc_readx(params->ssc->regs, params->pdc->xncr)); 223 224 ssc_writex(params->ssc->regs, SSC_IER, 225 params->mask->ssc_endx | params->mask->ssc_endbuf); 226 ssc_writex(params->ssc->regs, SSC_PDC_PTCR, 227 params->mask->pdc_enable); 228 229 pr_debug("sr=%u imr=%u\n", 230 ssc_readx(params->ssc->regs, SSC_SR), 231 ssc_readx(params->ssc->regs, SSC_IER)); 232 break; /* SNDRV_PCM_TRIGGER_START */ 233 234 case SNDRV_PCM_TRIGGER_STOP: 235 case SNDRV_PCM_TRIGGER_SUSPEND: 236 case SNDRV_PCM_TRIGGER_PAUSE_PUSH: 237 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, 238 params->mask->pdc_disable); 239 break; 240 241 case SNDRV_PCM_TRIGGER_RESUME: 242 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: 243 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, 244 params->mask->pdc_enable); 245 break; 246 247 default: 248 ret = -EINVAL; 249 } 250 251 return ret; 252 } 253 254 static snd_pcm_uframes_t atmel_pcm_pointer( 255 struct snd_pcm_substream *substream) 256 { 257 struct snd_pcm_runtime *runtime = substream->runtime; 258 struct atmel_runtime_data *prtd = runtime->private_data; 259 struct atmel_pcm_dma_params *params = prtd->params; 260 dma_addr_t ptr; 261 snd_pcm_uframes_t x; 262 263 ptr = (dma_addr_t) ssc_readx(params->ssc->regs, params->pdc->xpr); 264 x = bytes_to_frames(runtime, ptr - prtd->dma_buffer); 265 266 if (x == runtime->buffer_size) 267 x = 0; 268 269 return x; 270 } 271 272 static int atmel_pcm_open(struct snd_pcm_substream *substream) 273 { 274 struct snd_pcm_runtime *runtime = substream->runtime; 275 struct atmel_runtime_data *prtd; 276 int ret = 0; 277 278 snd_soc_set_runtime_hwparams(substream, &atmel_pcm_hardware); 279 280 /* ensure that buffer size is a multiple of period size */ 281 ret = snd_pcm_hw_constraint_integer(runtime, 282 SNDRV_PCM_HW_PARAM_PERIODS); 283 if (ret < 0) 284 goto out; 285 286 prtd = kzalloc(sizeof(struct atmel_runtime_data), GFP_KERNEL); 287 if (prtd == NULL) { 288 ret = -ENOMEM; 289 goto out; 290 } 291 runtime->private_data = prtd; 292 293 out: 294 return ret; 295 } 296 297 static int atmel_pcm_close(struct snd_pcm_substream *substream) 298 { 299 struct atmel_runtime_data *prtd = substream->runtime->private_data; 300 301 kfree(prtd); 302 return 0; 303 } 304 305 static struct snd_pcm_ops atmel_pcm_ops = { 306 .open = atmel_pcm_open, 307 .close = atmel_pcm_close, 308 .ioctl = snd_pcm_lib_ioctl, 309 .hw_params = atmel_pcm_hw_params, 310 .hw_free = atmel_pcm_hw_free, 311 .prepare = atmel_pcm_prepare, 312 .trigger = atmel_pcm_trigger, 313 .pointer = atmel_pcm_pointer, 314 .mmap = atmel_pcm_mmap, 315 }; 316 317 static struct snd_soc_platform_driver atmel_soc_platform = { 318 .ops = &atmel_pcm_ops, 319 .pcm_new = atmel_pcm_new, 320 .pcm_free = atmel_pcm_free, 321 }; 322 323 int atmel_pcm_pdc_platform_register(struct device *dev) 324 { 325 return snd_soc_register_platform(dev, &atmel_soc_platform); 326 } 327 EXPORT_SYMBOL(atmel_pcm_pdc_platform_register); 328 329 void atmel_pcm_pdc_platform_unregister(struct device *dev) 330 { 331 snd_soc_unregister_platform(dev); 332 } 333 EXPORT_SYMBOL(atmel_pcm_pdc_platform_unregister); 334 335 MODULE_AUTHOR("Sedji Gaouaou <sedji.gaouaou@atmel.com>"); 336 MODULE_DESCRIPTION("Atmel PCM module"); 337 MODULE_LICENSE("GPL"); 338